Wanted to see if anyone else is experiencing this problem.

I just installed this game and I can't start it. The very first time I started it, it did show the intro video and menu, but subsequent starts will only play the audio from the intro accompanied by a black screen, then when I click to interrupt the intro, the game switches back to my Windows desktop. I can switch back to the game but it gives me only a black screen and when I click a mouse button, the game switches back out to the desktop. The only way to quit the game is to kill the process.

System information: Windows 8.1 x64, 24GB RAM, Nvidia GTX660

EDIT: After starting the game a few times, it now shows properly most of the time (it seems to be a rather random problem) but I am no longer given the option to input my serial number, and I can't find an option for it in the menus. Will this affect the game?

EDIT2: I also installed S4 now. The same screen-switching problem affects GOG's release of Settler's IV but in that case it seems to be more of a waiting game as the desktop switching issues occur when starting the game but waiting for it to switch back and forth a few times on its own will bring up the menu and allow me to start the game. Still, a weird issue with both these games.